Noncoherent Multiuser Grassmannian Constellations for the Mimo Multiple Access Channel
Javier Álvarez-Vizoso, Diego Cuevas, Carlos Beltrán, Ignacio Santamaría, Vít Tucek, Gunnar Peters
Abstract
We consider the design of multiuser constellations for a multiple access channel (MAC) with K users, with M antennas each, that transmit simultaneously to a receiver equipped with N antennas through a Rayleigh block-fading channel, when no channel state information (CSI) is available to either the transmitter or the receiver. In full-diversity scenarios where the coherence time is at least T ≥ (K + 1)M, the proposed constellation design criterion is based on the asymptotic expression of the multiuser pairwise error probability (PEP) derived by Brehler and Varanasi in [1]. Although this PEP expression was previously considered intractable for optimization, in this work we derive a closed-form formula for its unconstrained gradient and perform Riemannian optimization in the Grassmannian manifold to design multiuser constellations for the MIMO MAC with state-of-the-art performance in terms of symbol error rate (SER).
BibTeX
@inproceedings{icassp2023_noncoherentmulti,
title = {Noncoherent Multiuser Grassmannian Constellations for the Mimo Multiple Access Channel},
author = {Javier Álvarez-Vizoso and Diego Cuevas and Carlos Beltrán and Ignacio Santamaría and Vít Tucek and Gunnar Peters},
booktitle = {ICASSP 2023},
year = {2023}
}